TL;DR
Guerrilla Mail and Mailinator are both veteran disposable email services that have been running for well over a decade. They have moved in different...
Aspect
Guerrilla Mail
Mailinator
Inbox Privacy
Private inboxes link to your browser session. Only you access your emails. Nobody else reads your inbox even if they know your address. Guerrilla Mail isn't risky for receiving verification codes, password resets or sensitive information. It's safe.
Free tier inboxes are public. Anyone who enters the same email address sees all messages. This creates a major security vulnerability for any signup involving sensitive information. You only get a private and secure inbox if you pay for a plan with custom domains.
Sending Capability
You can send outgoing emails with this service. This is a rare feature that is actually useful for disposable email providers. Deliverability can be inconsistent because many recipients filter messages from Guerrilla Mail servers. Even so, the ability to send is valuable for testing, basic two-way communication or situations where a service requires you to reply to an email.
All tiers are receive-only, even the paid plans. You can't send or reply to any emails. This creates a real limitation for use cases where a service requires email-based correspondence instead of just one-way verification.
Pricing Model
Nukemail is free and there isn't a paid tier available. The service stays running through modest advertising and has worked on this model since it started. You don't have a premium upgrade path because the free experience is the full experience.
The service has moved toward paid plans over the years. The free tier is getting limited because of restrictions on features and retention. Paid plans start at $79/month for teams. This price includes private domains, API access and configurable retention. Enterprise pricing goes higher for organizations with large-scale testing needs.
API Access
You can use the free public API at api.guerrillamail.com. The API is basic but it works for simple automation tasks like creating inboxes, checking for new messages and reading email content programmatically. It is a good choice for individual developers with simple needs.
Paid plans give you access to a professional-grade API. It is well-documented and includes SDKs, webhook support and enterprise-level reliability. Corporate QA teams use it for automated testing of email-dependent workflows. It is much more capable than the free API from Guerrilla Mail, but the $79/month entry price puts it in a different category.
Domain Blocking
Guerrilla Mail domain variants like Guerrillamail.com, guerrillamailblock.com, grr.la and others are blocked after 18+ years of operation. They don't work. These domains appear on every commercial blocklist so the service isn't reliable for signing up on mainstream websites.
The mailinator.com domain is well-known and blocked on most websites. Paid plans include custom private domains that aren't on public blocklists. This gives paying customers a real workaround to the domain blocking problem. That is one of the main reasons to choose the paid tier of Mailinator.
Custom Address Names
You pick your own inbox name. You decide what goes before the @. Because your inboxes are private, this gives you a secure way to manage your mail. You can create a memorable address and be sure that only your session can access it.
You can choose your own custom inbox names on the free tier. Because these inboxes are public, picking a custom name creates a security risk. If you use
[email protected], anyone who guesses or knows that address can read all your messages. The custom naming feature is rendered useless by the public inbox model.
Email Rendering
The email reader handles simple HTML messages well. It might struggle with complex marketing emails that use heavy CSS or table-based layouts. Plain text emails display reliably. You won't see attached images because the system doesn't display them.
It renders HTML emails well. It handles most formats correctly including complex marketing emails with formatting, images and clickable links. Its rendering quality beats Guerrilla Mail. This is better for testing email templates.
Verdict
Guerrilla Mail is a better free option for individual users. Private inboxes provide real security for receiving sensitive information. The ability to send mail is a unique feature that no other major disposable email service offers. Their free API is basic but provides developer value that Mailinator keeps behind a $79/month paywall.
Mailinator is worth considering only if you are willing to pay for the paid tier. The combination of private custom domains, a professional API and enterprise-level reliability makes it a real tool for QA teams and development organizations. But at $79/month and up, it is for a different audience than individual users looking for quick disposable email.
The real question is whether you need a free privacy tool like Guerrilla Mail or a paid professional testing platform such as Mailinator. If you are just using it for yourself, Guerrilla Mail is almost always the answer. If you are testing software as a team and have a budget for tools, the paid tier of Mailinator is a solid option.
Both services deal with the same domain blocking issues on their free tiers. NukeMail provides private inboxes and lets you pick your own address names just like Guerrilla Mail. It uses fresh domains to get around blocklists like the ones you find on Mailinator's paid tier and it does this for free. You get the best parts of both services without needing to pay a $79/month subscription fee.